to Hamburger Containerboard in Pitten, Austria
The Fascination of Paper
We produce advanced recycled containerboard to exceed customer expectations.
Dedicated to Customers' Success
We produce advanced recycled containerboard to exceed customers expectations.
- The Fascination of Paper
- Dedicated to Customers' Success
Paper mills are divided into three areas:
- Stock preparation
- Paper machine
The production process starts with the preparation of the stock. In this area, dried bales of recovered paper and/or cellulose are dissolved in a large amount of water and cleared from contaminants. The recovered paper is mainly acquired from private homes and department stores. Recycling recovered paper requires considerable cleaning efforts: The pulp is passed through a series of sieves with perforations and slits to entirely remove any kind of contamination.
In the final stage of the preparation, agents such as starch, dyes or fillers are used to obtain the desired paper qualities.
The processed pulp suspension then enters the paper machine where it is formed into a continuous sheet of paper. The paper machine is a continuous production facility of 100 meters and is divided into the following three main sections:
- Sieving section
- Press section
- Drying section
In first section, the processed pulp suspension is highly diluted to such an extent that every litre of the cellulose-water-mixture contains only 7 grams of fibre and fillers. Using a jet, this suspension is then evenly sprayed onto the entire width of a revolving wire. The water drains from the pulp or is suctioned off, and the recycled fibres begin to bond together to form a fibre fleece on the wire.
At the end of this so called sheet forming process, the moisture content of the paper web is still about 80%.
The paper machine at Hamburger Rieger paper mill Spremberg has three such sheet forming plants. Before entering the next stage of the process, its fibre fleeces are joined into a paper web. The resulting multiple layers of the paper web enable high-quality fibres to be used specifically for obtaining certain product qualities such as whiteness, strength etc.
The moisture content of the sheet is further reduced in the pressing section by applying hydraulic pressure. For this purpose, the paper web runs between felt-covered press rollers under high pressure. The result of the pressing process is a dry content of 52% and an increased strength of the paper web.
In the subsequent drying section, steam is used to remove the remaining water. This includes the paper web running over steam-heated drying cylinders in a zigzag pattern. In order to obtain specific strength and print properties, a unit applying starch and glue onto the paper surface is included in the drying section. The calender at the end of this section ensures a smooth surface and consistent thickness of the paper.
The paper machines in Trostberg and Spremberg also have a coating unit where the paper is refined additionally for a smoother and glossier surface.
After leaving the drying section within the paper machine, scanning frame systems perform a number of precise quality controls of the paper web. Different parameters such as thickness, colour, weight and´moisture content are measured and their consistency throughout the entire paper web are examined and documented.
The resultant paper web is wound onto steel rolls (tambour) at the end of the paper machine.
Before it is sent to the customer, the paper is cut to the desired length and width. The role cutting machine cuts the paper web into shorter rolls. The finished rolls are then packed and labelled according to the customer's request.